Degenerative arthritis of the carpus associated with congenital hypoplastic thumb

The case history of a young man with bilteral congenital hypoplastic thumbs and early degenerative arthritis involving the base of the thumb and scaphotrapeziotrapezoid joints is reported. To our knowledge this association has not been previously made. Limited intercarpal arthrodesis and/or trapezium arthroplasty may be required at a relatively early age in patients with thumb dysplasia. We believe the hypoplastic thenar musculature may lead to instability and excessive shear stresses on the radial side of the carpus, causing the early arthritic changes.